test, yaml: rework linkAndBindWikiData

1 files changed, 24 insertions, 3 deletions

diff --git a/test/lib/wiki-data.js b/test/lib/wiki-data.js
index 5433de2..d2d860c 100644
--- a/test/lib/wiki-data.js
+++ b/test/lib/wiki-data.js
@@ -1,12 +1,17 @@
 import CacheableObject from '#cacheable-object';
 import find from '#find';
+import {withEntries} from '#sugar';
 import {linkWikiDataArrays} from '#yaml';
 
 export function linkAndBindWikiData(wikiData, {
   inferAlbumsOwnTrackData = true,
 } = {}) {
-  function customLinkWikiDataArrays(...args) {
-    linkWikiDataArrays(...args);
+  function customLinkWikiDataArrays(wikiData, options = {}) {
+    linkWikiDataArrays(
+      (options.XXX_decacheWikiData
+        ? withEntries(wikiData, entries => entries
+            .map(([key, value]) => [key, value.slice()]))
+        : wikiData));
 
     // If albumData is present, automatically set albums' ownTrackData values
     // by resolving track sections' references against the full array. This is
@@ -43,7 +48,23 @@ export function linkAndBindWikiData(wikiData, {
 
     // Use this if you HAVEN'T mutated wikiData and just need to decache
     // indirect dependencies on exposed properties of other data objects.
-    // See documentation on linkWikiDataArarys (in yaml.js) for more info.
+    //
+    // XXX_decacheWikiData option should be used specifically to mark points
+    // where you *aren't* replacing any of the arrays under wikiData with
+    // new values, and are using linkWikiDataArrays to instead "decache" data
+    // properties which depend on any of them. It's currently not possible for
+    // a CacheableObject to depend directly on the value of a property exposed
+    // on some other CacheableObject, so when those values change, you have to
+    // manually decache before the object will realize its cache isn't valid
+    // anymore.
+    //
+    // The previous implementation for this involved overwriting the relevant
+    // wikiData properties with null, then replacing it with the original
+    // array, which effectively cleared a CacheableObject cache. But it isn't
+    // enough to clear other caches that depend on the identity of wikiData
+    // arrays, such as withReverseReferenceList, so now it replaces with fresh
+    // copies of the data arrays instead; the original identities don't get
+    // reused.
     XXX_decacheWikiData:
       customLinkWikiDataArrays
         .bind(null, wikiData, {XXX_decacheWikiData: true}),